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  <meta name="Generator" content="EditPlus®">
  <meta name="Author" content="">
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  <title>Document</title>
	<!--html提供了一个标签，script-->
	<script>
		//定义和赋初值一起
		var a = 100;
		console.log(a); //100;

		//改变变量值
		var b = 800;
		
		//重新赋值了
		a = 300; //
		console.log(a); //300

		//a = b; //a=800
		b = a; //b=800
		console.log(a,b);
	</script>
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